This research proposal is designed to enable continued participation in the Primary Breast Cancer Therapy Group -- NSABP. The overall specific aims of the NSABP are to improve disease-free survival and survival in patients with primary operable breast and colorectal cancers. (See the NSABP Headquarters grant application for protocol rationale and overall scientific achievements to date) The Hotel-Dieu of Montreal has been an NSABP Member since July 1981 and is currently following 314 patients on long term adjuvant protocols. We expect to increase patients accrual to 75 per year. The entry of these patients into NSABP protocols will enable a more rapid and effective evaluation of current therapeutic regimens and will provide information for the design of future studies. The Hotel-Dieu of Montreal has been the second highest accrual in NSABP B-18 with 70 patients. Protocol B-18 is a high priority protocol of the NCI. Our breast ranking was 1st among 20 Grants with a perfect score of 100% in the NSABP evaluation score as of 12/31/90.